Over the past decades the impact of construction on the primary energy consumption and greenhouse gas emissions has highlighted [1]. The interest of the international scientific community has therefore focused on the concept of a Net Zero Energy Solar Building (NZESB), which is generally defined as a building that produces all primary energy it needs during a year [2]. Among the many research activities focused on these buildings, it should be mentioned the case study developed within the IEA SHC Task 40/ECBS Annex 52 "Towards Net Zero Energy Solar Buildings". The paper shows a case study of a Net Zero Energy Building (NZEB) located in Ancona (Italy):“Life Energy And Future (Leaf) House” (LH). This building produces energy from renewable sources with the aim to cover the energy annual needs. After a detailed description of the case study, authors show the methodological approach adopted in the design phase, including the analysis of the environmental condition of the house given by a sensors system which monitors temperature, humidity, CO2 level, energy consumption and energy production. The paper presents the results of the analysis of the first year of monitoring phase concerning the energy consumption and production of the house.